An operating button can output light rays to the outside of the operating button via a light source provided therein, so as to identify the state of the operating button or a device. Because of the limitation of the volume and structure of the operating button, when in operation, the output light rays of the operating button have a long light path such that the brightness of the output light rays is insufficient. In addition, the light rays output by the operating button are not in parallel such that the light rays irradiated thereby are not even and have light spots.